Method for production of sheet metal components

ABSTRACT

A process includes producing a group of automotive components by forming components having various global geometries via a common tooling configured to bend a blank sheet of metal to create a variable cross section profile, forming an addendum as an integral portion of each formed component, and altering the global geometries in a series of incremental deformations to create local geometries while each component is affixed to a deforming machine via the addendum.

TECHNICAL FIELD

The disclosure relates to a production method of sheet metal components.

BACKGROUND

Prototype vehicles as well as niche and premium vehicles create a need for manufacturing of parts in low volumes. Such manufacturing presents a set of challenges. For example, the tooling which is tailor-made for each individual part is expensive, and it is time consuming to produce such tooling. In addition, frequent design changes require update of the tooling on a regular basis. Yet, traditional manufacturing techniques may not accommodate the needs associated with the design changes. As a result, some design changes may not be incorporated into the prototypes due to the manufacturing limitations. Some manufacturing processes such as incremental forming are too slow, and processes such as flexible roll-forming require significant design concessions to be useful.

SUMMARY

In at least one embodiment, a process of producing a group of automotive sheet metal components is disclosed. The method includes producing a group of automotive components by forming components having various global geometries via a common tooling configured to bend a blank sheet of metal to create a variable cross section profile. The process includes forming an addendum as an integral portion of each formed component. The process also includes altering the global geometries of the components in a series of incremental deformations to create local geometries while each component is affixed to a deforming machine via the addendum. The group of automotive components may include one component type designated for different vehicle types. The component type may include an underbody member, a roof cross member, a rail, or a rocker member. The group of automotive components may include different component types designated for one vehicle type. The sheet metal component may have a longitudinal profile. The variable cross section profile may include a variable height cross section. The addendum may extend beyond the global geometry of the component. The addendum may have a shape universal for each component of the group of the components. The addendum may be removed after formation of the local geometries. The global geometries and the local geometries may be created separately via different tooling.

In another embodiment, a method of producing a group of various automotive longitudinal components is disclosed. The method includes utilizing a common tool to form a variable cross section profile by bending a sheet metal for each component of the group in a first process. The method may further include connecting each deformed metal sheet to a removable section. The method may include altering the profile of the deformed metal sheet in a series of incremental deformations in a second process to create the longitudinal component while the sheet metal is attached to a deforming machine via the removable section. The first and second processes may be performed by different machines and tooling. The bending may form depressions in a vertical surface of the sheet metal. The incremental deformations may include bending a horizontal surface of the sheet metal. The removable section may be laser trimmed after the second process. The first process may utilize flexible roll forming and the second process may utilize incremental forming.

In yet another embodiment, a process of forming automotive sheet metal components is disclosed. The method may include creating a global geometry of a first longitudinal sheet metal component by forming a variable cross section profile in a blank sheet of metal. The method may include altering the global geometry of the first component in a series of incremental deformations to create local geometries. The method may further include creating global and local geometries of a second component by utilizing tooling which formed the first component, wherein the first and second components differ. The first and second components may be longitudinal components having at least one different dimension. The first and second components may be roof side railings having at least one different portion of the profile. The first and second components may differ in length, height, depth of depression of at least one portion of the components, or a combination thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-1F depict perspective views of exemplary components manufactured in accordance with one or more embodiments;

FIG. 2 schematically depicts a sequence of steps of the disclosed manufacturing process capable of producing longitudinal components with variable cross section;

FIGS. 3A-3C depict perspective views of an example component with example addendums.

DETAILED DESCRIPTION

Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments may take various and alternative forms. The figures are not necessarily to scale; some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures may be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.

Except where expressly indicated, all numerical quantities in this description indicating dimensions or material properties are to be understood as modified by the word “about” in describing the broadest scope of the present disclosure.

The first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation. Unless expressly stated to the contrary, measurement of a property is determined by the same technique as previously or later referenced for the same property.

Certain vehicle prototypes, as well as niche and premium vehicles, and other automotive projects require parts manufactured in low volume. Because of the relatively low amount of such parts to be produced, the parts are typically made using tooling which is tailor made for the parts and discarded after making a relatively small batch of the parts. While the material used for such tooling is typically cheaper than materials used for high-performance and high-volume tooling, production of the tooling remains expensive and time consuming.

Example tooling for the low volume parts may be kirksite tooling incorporating dyes made from relatively non-expensive alloys. Yet, during a product development process, design changes are common and the traditional tooling may not accommodate for the projected changes or respond to the design changes. As a result, some design changes may not be incorporated into the prototypes to decrease the cost and process time.

Some of the low volume parts include a variety of sheet metal parts. Traditional manufacturing techniques are either unsuitable for production of the sheet metal such as additive manufacturing or incapable of providing sufficient detail required for the automotive parts. For example, traditional roll forming is capable of producing only profiles with a constant cross-section in the longitudinal direction. In addition, traditional tooling cannot be used to produce more than one component from a family of components. Thus, each part requires a separate tooling which is impractical from financial and production standpoint.

According to one or more embodiments, a process for producing automotive metal sheet components is provided. The process implements a combination of two separate processes. The first process enables creating a global geometry of the component. Global geometry relates to a rough shape of a component without defining its fine features. The global geometry is subsequently altered by a second process which defines the fine features and details in the global geometry. To enable the transition from the first process to the second process, the component includes an addendum while or after having the global geometry sculpted.

Typically, the components are produced by methods such as press forming which requires large expensive tooling and material which does not have sufficient longevity. The two processes disclosed herein work in a synergistic manner to produce components of specific geometries in an economical and time-saving manner. The same tooling may be used to produce a variety of components within the same family or for the same vehicle type on a single production line. Grouping components which have similar characteristics and producing them using the same tooling provides time savings of several days to weeks and is more economical.

In at least one embodiment, the process includes producing a group or family of automotive components by forming components having various global geometries while utilizing a common tooling configured to bend a blank sheet of metal to create a variable cross section profile. The process includes forming an addendum and/or adding a fixture to each formed component. The process also includes altering the global geometries of the components in a series of incremental deformations to create local geometries while each component is affixed to a deforming machine via the addendum and/or fixture.

The component 10 may be any metal sheet component. Example components 10 are depicted in FIGS. 1A-1F. As can be seen in the examples of FIGS. 1A-1F, the component 10 may be a longitudinal component having greater dimensions along longitudinal axis x than along axis y or z. The components 10 may have a cross-section that is discontinuous or variable on the longitudinal axis x, but may also vary along axis y, and/or z. The components 10 may have one or more ends 12 which are closed or open. The components 10 may have one or more sections 14 which differ in dimensions from at least one other section 16 or plurality of sections, and the like. The components 10 may have one or more bends, arches, or curves 18. In addition, or in the alternative, the components 10 may have one or more apertures 20. The apertures 20 may be symmetrically or asymmetrically spaced within the metal component body 22. The apertures may have any size, shape, or form. For example, an aperture 20 may be regular, irregular, circular, oval, polygonal, square, rectangular, or have another shape. The apertures 20 within the same component 10 may have the same or different shape and/or dimensions. A component 10 may be free of any aperture. A component 10 may have varying length, height, thickness, or a combination thereof within its body 22. The component 10 may have a base 24, sides 26, and one or more flanges 28.

The component 10 may have a cross-section having a varying profile. The cross section may vary in longitudinal direction. The profile may have a variable width, depth/height, or a combination thereof. The profile may be fully open, partially open, or closed. The profile may be shaped like U, 0, V, D, or C. The profile may be symmetrical or asymmetrical.

The components 10 may be categorized as belonging to various families of components. The components 10 may be categorized by a component type or a vehicle type. Thus, a group or family of components to be produced by a common tooling may include the same type of component for at least two different vehicle types. Alternatively, a group of components to be produced by a common tooling may include different members for the same vehicle type. Table 1 below provides examples of grouping of component families and vehicle types. The amount and type of components and vehicle types are just examples. Other types of components and different types of vehicles may be included.

TABLE 1 Component families and vehicle types Component Families Roof Under- Rocker Side body Reinforce- Center Vehicle Rail Sled X ment Front Roof Rear Type Outer Runner Member Member Header Bow Header 1 a1 b1 c1 d1 e1 f1 g1 2 a2 b2 c2 d2 e2 f2 g2 3 a3 b3 c3 d3 e3 f3 g3 4 a4 b4 c4 d4 e4 f4 g4 5 a5 b5 c5 d5 e5 f5 g5

For example, a common tooling may be used to produce a component family of roof side rail outer members a1-a5 for vehicle types 1-5. For example, a family of components 100, 102, 104 depicted in FIG. 1A-1C contains three different roof side rail outer members from the group a1-a5. Another example family includes various components 202, 204 categorized as a sled runner, which are depicted in FIGS. 1D and 1E. An example component 304 depicted in FIG. 1F belongs to the family of underbody X members c1-c5. Other example component families may include rocker reinforcement members, front headers, rear headers, center roof bow components, cross members, or the like. Each family may include the same type of a component for a variety of vehicle types or models. For example, a family may contain sled runners for at least two different types of vehicle models, as is illustrated in the Table 1 above.

Alternatively, another common tooling may be used to produce a family of components a1-g1 for the common vehicle type 1. And yet another tooling may be used to produce a series of components a5-g5 for the common vehicle type 5.

Different components within the same family may have the same or different profile, dimensions such as overall height, length, width, geometry, the amount, shape, and/or size of apertures, base section width, side wall height, flange width, and the like.

The material of the components 10 may be various grades of steel. For example, the material may be low strength, high strength, and ultra-high strength steel, austenitic, ferritic, or martensitic grade steel, an alloy steel containing Mn, Si, Ni, Ti, Co, Cr, and/or Al in various proportions, carbon steel, or tool steel.

A software may be utilized to determine the most economical efficient and economical manner of grouping various components into families. Once the group of components to be produced is determined, all of the components of the group may be formed in the first process before the components are finalized in the second process. For example, if the group contains components a1-g1 for the vehicle type 1, all of the components of the group will be formed in the first process before proceeding to the second process. The desired number of components a1 may be formed first, followed by the desired number of components b1, followed by the desired number of components c1, etc. Once all of the components a1-g1 have been formed in the first process, the components a1-g1 may proceed to the second process. Thus, the components a1-g1 may be produced consecutively such that a1 components are produced before b1 components are produced, followed by production of c1, d1, e1 components, etc. Alternatively, it may be desirable to form a certain amount of any component within the group a1-g1, such that a certain amount of components a1 is produced in the first process, then a certain amount of component c1 is produced, followed by a certain amount of component a1 again. Alternatively still, the components a1-g1 may be produced in any order.

The same principles apply if the group contains the same type of component for different vehicle types, for example if the group includes roof side railings a1-a5 for vehicles types 1-5.

The first process 500, schematically depicted in FIG. 2, forming the global geometry or the rough shape of the component 10 enables contouring of blanks in such a way that the components may have a cross-section which is discontinuous on the longitudinal axis. The first process may be, for example, flexible roll forming, also called 3D-roll forming. Flexible roll forming is a progressive motion process utilizing a machine 502 employing a variety of rolls 504 which are independently movable and are capable of contouring the discontinuous cross section in the metal sheet without a tool change. A plurality of rolls 504 progressively bends a metal sheet 506 into a final predefined shape. The first process may shape a flat metal sheet along the longitudinal axis into a convex or concave strip. The first process may utilize a plurality of independent rolls 504, each capable of forming an incremental part of the global geometry in steps, all the rolls 504 together forming the global geometry of the component 10. The first process may provide sequential or continuous bending operations. Up to about 50%, 60%, 70%, or 80% of the overall shape or contours of the metal component 10 may be formed via the first process. The first process may include creating deformations in vertical, horizontal, or both surfaces of the component 10. The first process may utilize the same set of rolls 504 to produce global geometries of different components. The first process may utilize the same set of tools (rolls 504) to form global geometries of all the components within at least one family.

The thickness of the metal sheet entering the first process machine may be up to 7 mm. The thickness may be about 1, 2, 3, 4, 5, 6 or 7 mm. The thickness may vary throughout the component 10 before the first, second process, or after the second process. The metal sheet material may have up to 500 MPa yield strength. The metal sheet may be precut to one or more strips.

The dimensions of the metal sheet entering the first process machine may be sufficient such that one or more addendums 30, described below, may be formed as integral portions of the component 10.

The second process 600, as depicted in FIG. 2, is performed on a different machine 602, utilizing different tooling than the first process. The second process enables alteration of the global geometry to form detailed contours in the global geometry of the component 10 which the first process may not be suitable to form for a variety of reasons. For example, creating local geometry with the first process would be time consuming. Additionally, attempting to define local geometry with the first process may result in warping or undesirable stresses in the material. Yet, the second process may not be suitable to form the global geometry. For example, the material properties such as ductility may pose limitations such that the second process may not be able to provide sufficient bending operations. Thus, the synergic use of the first process to shape the global geometry while utilizing a second process, which differs from the first process, to provide the local or detailed geometry in the preformed global geometry results in a faster, more economical method of producing metal sheet longitudinal components with intricate geometries and with increased bearing capacity as well as reduced structural weight when compared to similar components produced by different methods. The second process 600 may utilize the same tooling or set of tools to provide local geometries of a plurality of or all components of the same family.

To allow for the transition from the first process to the second process, and/or processing of the component 10 in the second process, one or more addendums 30 and/or fixtures 32 may be formed as part of or attached to each component 10. Example addendums 30 are depicted in FIGS. 2 and 3B, as portions of the formed component 10. The shape of the addendum 30 may be specific to each part, or the same addendum 30 may be formed on more than one member of each component family. The addendum 30 and/or fixture 32 allows for attachment of the component 10 to the second process machine without compromising the quality of the part. By providing the addendum 30 and/or fixture 32, the component 10 itself receives less contact with the processing machine. As a result, the component's 10 surface is less prone to obtain scratches, dents, marks, and/or other imperfections which could otherwise result from the transition between the first and second process and/or from the process machines themselves.

The addendum 30 and/or fixture 32 may have any shape or form as long as the addendum 30 and/or fixture 32 provides sufficient support for the component 10. As is depicted in FIG. 2, the addendum 30 may be an extension of at least one side, flange, or base of the component 10. The addendum 30 may run along the entire length of the side or flange. Alternatively, the addendum 30 may be formed on only a portion of the side, flange, or base. Both the fixture 32 and/or the addendum 30 may have the same or different dimensions than a component 10. For example, the addendum 30 and/or fixture 32 may have the same length as the component 10, or be longer or shorter than the component 10. The addendum 30 and/or fixture 32 may have a length which extends beyond the global geometry of the component 10. More than one addendum 30 may be formed on the same component 10, as is shown in FIGS. 2 and 3B. Similarly, more than one fixture 32 may be used to support the component 10.

In at least one embodiment, the shape of the addendum 30 may be a shape common to at least two different addendums 30 of at least two different components 10 or to all components of at least one family of components 10. The addendum 30 may be a universal addendum for each component of a family of components 10.

Unlike the addendum 30, which forms an integral portion of the component 10 formed in the first process, the fixture 32 does not form an integral portion of the component 10. The fixture 32 may be added after the first process. The fixture 32 may be reused or be used just once. The same fixture 32 may be used for variety of components within its family. Alternatively, the same fixture 32 may be used for production of a plurality of the same components within the same family.

The addendum 30 and/or fixture 32 may be temporarily affixed to or connected to the component 10 such that the addendum 30 and/or fixture 32 is removable. The addendum 30 may form an integral portion of the component 10. The addendum 30 and/or fixture may be in contact with or be attached to the second process machine via one or more apertures, for example one or more apertures 20 which are provided in the component 10 for other purposes. Alternatively, or in addition, the apertures 20 may be created specifically for the purpose of attaching the addendum 30, and/or fixture 32 to the second process machine, to the component 10 (for fixture), and/or the second process machine. Alternatively, or in addition to the apertures 20, the addendum 30 and/or fixture 32 may be affixed second process machine and/or to the component 10 for (fixture) via one or more hooks, bolts, screws, clamps, connectors, brackets, clasps, fixtures, or the like 34.

The addendum 30 and/or fixture 32 may be in contact with the component 10 during or after the component 10 receives its global geometry during the first process, between the first and second processes, during or after the component 10 is being shaped to receive its local geometry features in the second process, or a combination thereof. For example, the addendum 30 may be formed as an integral part of the component 10 during the first process before exiting the first process machine 502. Alternatively, an addendum 30 and/or fixture 32 may be attached to the component 10 after the global geometry of a certain portion of the component 10 is formed and before the entire global geometry is formed.

The addendum 30 and/or fixture 32 may be made from a metal, composite, polymer, wood, glass, or a combination of materials. The thickness of the addendum 30 and/or fixture may be the same or different than the thickness of the component 10. For example, a metal addendum 30 and/or fixture 32 may have a greater or smaller thickness than the component 10 to be supported. For example, the addendum 30 and/or fixture 32 may be less malleable and/or have higher strength than the component 10 as a result of the different material thickness. The fixture 32 may be made from a different metal material than the component.

The addendum 30 and/or fixture 32 may be removed after the second process. For example, the addendum 30 may be removed by laser trimming.

The transition from the first process 500 to the second process 600 may be done manually or robotically. After the component 10 is transported to the second process machine 602, the local geometry is being formed. The second process may be, for example, incremental sheet forming, which forms detailed contours in the preformed global geometry. The second process employs a machine 602 capable of indenting the preformed global geometry in a series of incremental deformations. The contouring tool may indent the metal into a certain depth and follow a contour, another indent may follow with drawing the next contour, etc. The addendum 30 and/or fixture 32 may be used to attach the component 10 to the second process machine. For example, the component 10 may be clamped to the second process machine in the xy axis such that the component 10 is free to move along the z axis. Up to about 50%, 40%, 30%, or 20% of the overall shape or contours of the metal component 10 may be formed via the second process. The second process may include forming depressions, deformations, bending, indentations, and/or the like in the vertical, horizontal, or both surfaces of the component 10.

During the first process, second process, or before or after either the first or second process, additional operations may be performed on the component 10 and/or the addendum 30. For example, one or more apertures 20 may be created in the component 10 by a variety of techniques such as punching or by a laser. Laser trimming may be employed to form one or more flanges 28, remove or reshape the addendum 30, or both.

The first process machine, the second process machine, and additional machines providing laser trimming, hole punching, transportation from the first process station to the second process station, or the like may be connected to one or more controllers. The one or more controllers may have one or more processing components such as one or more microprocessor units which enable the controllers to process input data. The input data may include information about individual components, individual families of components, material and dimensions of the components, desired global geometry of each component, desired local geometries of each component, dimensions and placement of the addendums, position and dimensions of the apertures and/or flanges. The input data may further include information about individual rollers of the first process machine, their dimensions, position, angle as well as the desired location of each roller during the first process, providing a series of deformations resulting in the global geometry of each component 10. The input data may further include information about the path of the deforming tool during the second process providing the local geometries of each individual component.

The one or more controllers may be programmed to identify and categorize various families of components, initiate the first process and/or the second process, stop or temporarily interrupt either process, coordinate processing of individual components, forming of apertures, flanges, or the like. The controllers may be further programmed to switch the tooling paths of the first and second processes based on which component of which family is to be formed. For example, the controllers may be programmed to produce certain amount of component a1 from family 1, followed by certain amount of component a2 from family 1, and certain amount of component a3 from family 1, followed by certain amount of component b1 from family 2, component b2 from family 2, etc.

The method involving the two phase process for production of a variety components within the different families of longitudinal metal sheet components may include identifying and categorizing families of individual components. The method may further include developing tooling for the first process for each family of components. The first process tooling may then be utilized to achieve global geometry of each component in the family. The method may further include developing addendums for transportation of the components between the first and second process and during the second process, the addendum being specific to a family or to a specific component within a family. Simulation verifying feasibility of at least the first process and/or the second process may be performed. Based on the desired local geometries of each part within a family, tool paths of the second process machine may be developed. The second process may then be utilized to complete the overall geometry of each component. Laser trimming and/or hole punching is also contemplated.

The development of tooling for the first process may include performing simulations for each part of each family and verifying feasibility of production. The method may further include development of the first process tooling based on the first process machine line capabilities. Pre-processing requirements such as the required developed blanks, pre-punching, laser trimming, or the like may be identified.

The method may include changing tooling or the first and/or second process machine after a desirable amount of components from one family were produced such that components from a different family may be produced.

The processes, methods, or algorithms disclosed herein may be deliverable to or implemented by a processing device, controller, or computer, which may include any existing programmable electronic control unit or dedicated electronic control unit. Similarly, the processes, methods, or algorithms may be stored as data and instructions executable by a controller or computer in many forms including, but not limited to, information permanently stored on non-writable storage media such as ROM devices and information alterably stored on writeable storage media such as floppy disks, magnetic tapes, CDs, RAM devices, and other magnetic and optical media. The processes, methods, or algorithms may also be implemented in a software executable object. Alternatively, the processes, methods, or algorithms may be embodied in whole or in part using suitable hardware components, such as Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), state machines, controllers or other hardware components or devices, or a combination of hardware, software and firmware components.

The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments may be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics may be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes may include, but are not limited to cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for particular applications. 

What is claimed is:
 1. A process comprising: producing a group of automotive components by forming components having various global geometries via a common tooling configured to bend a blank sheet of metal to create a variable cross section profile; forming an addendum as an integral portion of each formed component; and altering the global geometries in a series of incremental deformations to create local geometries while each component is affixed to a deforming machine via the addendum.
 2. The process of claim 1, wherein the group of automotive components comprises one component type designated for different vehicle types.
 3. The process of claim 2, wherein the one component type comprises an underbody member, a roof cross member, a rail, or a rocket member.
 4. The process of claim 1, wherein the group of automotive components comprises different component types designated for one vehicle type.
 5. The process of claim 1, wherein the component has a longitudinal profile.
 6. The process of claim 1, wherein the variable cross section profile comprises a variable height cross section.
 7. The process of claim 1, wherein the addendum extends beyond the global geometry of the component.
 8. The process of claim 1, wherein the addendum has a shape universal for each component of the group of the components.
 9. The process of claim 1, wherein the addendum is removed after formation of the local geometries.
 10. The process of claim 1, wherein the global geometries and the local geometries are created separately via different tooling.
 11. A method comprising: producing a group of various automotive longitudinal components by utilizing a common tool to form a variable cross section profile by bending a sheet metal for each component of the group in a first process; connecting each deformed metal sheet to a removable section; and further altering the profile of the deformed metal sheet in a series of incremental deformations in a second process to create the longitudinal component while the sheet metal is attached to a deforming machine via the removable section.
 12. The method of claim 11, wherein the first and second processes are performed by different machines and tooling.
 13. The method of claim 11, wherein the bending forms depressions in a vertical surface of the sheet metal.
 14. The method of claim 11, wherein the incremental deformations include bending a horizontal surface of the sheet metal.
 15. The method of claim 11, wherein the removable section is laser trimmed after the second process.
 16. The method of claim 11, wherein the first process utilizes flexible roll forming and the second process utilizes incremental forming.
 17. A process of forming automotive sheet metal components, the process comprising: creating a global geometry of a first longitudinal sheet metal component by forming a variable cross section profile in a blank sheet of metal; altering the global geometry of the first component in a series of incremental deformations to create local geometries; and creating global and local geometries of a second component by utilizing tooling which formed the first component, wherein the first and second components differ.
 18. The process of claim 17, wherein the first and second components are longitudinal components having at least one different dimension.
 19. The process of claim 17, wherein the first and second components are roof side railings having at least one different portion of the profile.
 20. The process of claim 17, wherein the first and second components differ in length, height, depth of depression of at least one portion of the components, or a combination thereof. 